Which muscle group is primarily worked in the Hundred exercise?

The Hundred exercise is primarily focused on engaging and strengthening the abdominal muscles. In this classic Pilates exercise, the abdominals are required to work dynamically to maintain a stable spine and pelvis while performing a rhythmic pumping of the arms. This engagement helps to not only build core strength but also enhance endurance and coordination through controlled breathing.

Throughout the exercise, the activation of the abdominals is crucial for maintaining proper form and preventing strain on the lower back. The Hundred also encourages a deepening of the breath, which can further facilitate core engagement. This strong focus on the core makes the abdominals the primary muscle group targeted during the exercise, enhancing core stability and overall body awareness.